--- a/Makefile
+++ b/Makefile
@@ -40,7 +40,8 @@ NPERSHELF=16
 CONF_SCRIPTS = aoe-discover aoe-interfaces aoe-mkshelf aoe-revalidate aoe-flush aoe-stat
 PROGS = aoeping aoecfg aoe-sancheck
 COMMANDS := ${CONF_SCRIPTS} aoe-mkdevs aoe-version coraid-update ${PROGS}
-CFLAGS = -Wall -O -g
+# We could still override this on the command line.
+CFLAGS += -Wall -O -g
 SANCHECKLIBS = -lpthread
 
 AOE_PING_OBJ = aoeping.o linux.o